<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<!--[if IE]><script type="text/javascript" src="../excanvas.js"></script><![endif]-->
	</head>
	<!--
    兼容ie 6 7 8   ExplorerCanvas 是一个让ie浏览器支持canvas的开源插件
    -->
	<body>
			<canvas id="canvas" style="border: 1px solid #aaa; display: block;margin: 50px auto;">
			当前浏览器不支持canvas
		</canvas>
	</body>
	<script>
		var canvas = document.getElementById("canvas");
		canvas.width =800;
		canvas.height=800;
		
		var context = canvas.getContext("2d");
		if(context.ellipse){//判断具体属性支不支持
			context.beginPath();
			context.ellipse(400,400,300,200,0,0,Math.PI*2);//椭圆
			context.stroke();
		}else{
			alert("no ellipse");
		}
	</script>
</html>
